The compound UT-15 is a known compound disclosed in U.S. Pat. No. 4,306,075 in example 33. UT-15 is a synthetic analog of epoprostenol, a prostaglandin F.sub.1. The activities ascribed to the various compounds of this patent include inhibition of platelet aggregation, reduction of gastric secretion, and bronchodilation. It is indicated that the compounds of this patent have useful application as anti-thrombotic agents, anti-ulcer agents, and anti-asthma agents.
U.S. Pat. No. 5,153,222 discloses the use of UT-15 and related compounds to treat pulmonary hypertension.
Prostaglandin E.sub.1 has been found to increase walking distance in a small but statistically significant group of patients with peripheral arterial occlusive disease. However, since this drug is rapidly inactivated in the lungs, it must be administered intra-arterially, which leads to numerous harmful side effects. See Belch et al., Circulation, 95(9): 2298-2302 (1997). Belch further discloses the use of AS-013, a prostaglandin E.sub.1 prodrug, to treat peripheral arterial occlusive disease, presenting as intermittent claudication.
Okuda et al., Prostaglandins, 52(5): 375-384 (November 1996) showed that beraprost sodium, a stable analogue of prostaglandin I.sub.2, increased the cross-sectional area and the blood flow index of the dorsal pedis artery in non-insulin dependent diabetes patients. In addition, Okuda showed an increase in the dermal microcirculatory blood volume of these patients.
Patterson et al., Amer. J. of Cardiology, 75(1995): 26A-33A, have shown the vasodilator effects of UT-15 in patients with class III or class IV heart failure.